Research And Simulation On Physical Downlink Control Channel In LTE

Long Time Evolution is the new generation of wireless communication technologyand it is proposed by3GPP organization and its research is also led by3GPP. LTEsystem adopts orthogonal frequency division multiplexing and multiple-inputmultiple-output technology, the speed of data transimission and the spectrumeffectiveness are enhanced remarkably. LTE supports a variety of boardwidth allocationand improves the system capacity and coverage. LTE physical downlink control channelcarries the downlink control information, DCI contains mutiple terminal’s schedulinginformation and other control information. User Equipment must process a blinddetection in PDCCH to achieve the DCI of itself, so that it can receive thecommunication information from the eNodeB.This paper studies the transmitting and receiving process of DCI. By studying LTEspecification and conference draft published by3GPP and related essays, research ismade on LTE subframe structure, resource grid and so on. An intensive research is alsomade on DCI format and function. After making a large amout of research preparationon PDCCH process, simulation platform is complete on Matlab. On the PDCCHsimulation platform, some simulations with different parameters are performed tocompare the performance of LTE PDCCH. Theses parameters include CCE aggregation,the number of OFDM occupied by PDCCH and the number of antennas. From thecomparative result of simulation, it can be concluded that the block error rate of thePDCCH decreases with the increasing of CCE aggregation.and the throughput ofsystem increases with the increasing of the number of OFDM symbol occupied byPDCCH.Because the format and the size of PDCCH is important to the performance of thesystem, the design of the PDCCH resource allocation scheme is meaningful. Based ontwo traditional PDCCH resource allocation scheme, this paper designs a new scheme.By simulation and anylasis, new scheme can meet the demand of CCE block probilityand CCE utilization and fill the shortage of two traditional method.